TMPRSS6 (Transmembrane Protease, Serine 6) gene encodes TMPRSS6, also known as matriptase-2, a type II serine protease. It is primarily expressed in the liver, although high levels of TMPRSS6 mRNA are also found in the kidney, with lower levels in the uterus and much smaller amounts detected in many other tissues (Ramsay et al., Haematologica (2009), 94(6), 840-849). TMPRSS6 plays a role in iron homeostatis by binding and proteolytically degrading the hepcidin activator and BMP co-receptor HJV (hemojuvelin), which causes down-regulation of hepcidin levels.
TMPRSS6 consists of a short N-terminal intracytoplasmic tail, a type II transmembrane domain, a stem region composed of two extracellular CUB (complement factor Cls/Clr, urchin embryonic growth factor and BMP (bone morphogenetic protein)) domains, three LDLR (low-density-lipoprotein receptor class A) domains, and a C-terminal trypsin-like serine protease domain. There are also consensus sites for N-glycosylation in the extracellular domain, and a potential phosphorylation site in the intracytoplasmic tail region.
Numerous disorders can be associated with iron overload, a condition characterized by increased levels of iron. Iron overload can result in excess iron deposition in various tissues and can lead to tissue and organ damage. Accordingly, methods for effective treatment of disorders associated with iron overload are currently needed.